Drafting device



y 9, 1966 w. N. TWIST, JR 3,261,098

DRAFTING DEVIC E Filed Aug. 23, 1963 2 Sheets-Sheet 1 I NVENTOR WORTH1v. TW/$7',JR.

A 4 ORNEYS July 19, 1966 w, N, Twls'r, JR 3,261,098

DRAFTING DEVICE Filed Aug. 23, 1963 2 Sheets-Sheep 2 INVENTOR WORTH N.TWl$T,J/?.

United States Patent 3,261,08 DRAFTING DEVICE Worth N. Twist, J12, 1136York St., Apt. 304, Denver, Colo. Filed Aug. 23, 1963, Ser. No. 304,2874 Claims. (CI. 33-18) The invention herein described and claimed may bemanufactured and used by or for the Government of the United States ofAmerica for governmental purposes without the payment of royaltiesthereon or therefor.

This invention relates to a drafting instrument, and is moreparticularly concerned with an inking device for drawing extendedlengths of relatively closely spaced, parallel lines in the nature ofthose used on maps or the like, to represent roads or railroads.Drafting devices previously applied for this purpose have been made withsuch conventional writing structures as ruling pens, or as shown inPatent No. 2,394,452, issued to C. R. Howard on February 5, 1946, penscomprising ordinary pen points. Those employing such pens are familiarwith the drawbacks inherent in their use, among which are a short inksupply, and a need for cleaning after nearly each stroke, as well assharpening after relatively brief intervals of use. In improving overthe prior art, the device of the instant invention has for its writingstructure a manipulatable support element in which a pair of Rapidographor similarly constructed pens are maintained in positions which adaptthem to the task of drawing parallel lines of uniform thickness wherebythey produce road representations of high quality. Characteristic ofRapidograph or similarly constructed pens are their relatively large,free flowing ink supplies, and the ease with which they can bemaintained for immediate use. A description of an early form of thissort of pen can be found in Patent No. 1,409,037, issued to R. P.Starkey et al. on March 7, 1922. As disclosed by the patent, the pencomprises an ink fount or reservoir through whose center passes a springloaded plunger having a reduced part extending by way of an ink duct inthe lower end of the reservoir, slightly beyond and outside the latter.The exposed end of the extended part acts as a stylus or writing tip,and a further part thereof in the ink duct allows the plunger to act asa valve which functions to permit a controlled flow of ink from thereservoir to the writing tip only when the latter is lightly depressedagainst the spring load on the plunger. Since such pens remain operablewithout frequent interruptions for cleaning and filling, they are veryeffective for drawing extended lengths of double lines used in formingroad representations.

However, important advantages obtained by the utilization of thedrafting device according to the present invention follow from thefacile adjustments of its Rapidograph or similarly constructed pens inrespect to their support structures, made possible by the unique adaptermeans built into this device. Hereinafter described are several forms ofsuch adapter means which obtain an adjustability for the device thatallows it to be set for drawing parallel lines following anypredetermined curvature, and whose interlinear distance is selectablefrom within a relatively wide range of line spacings.

It is therefore a primary object of the present invention to provide anadjustable and convertible drafting instrument which is especiallyuseful for producing road indicating parallel lines of consistent weightand quality upon maps and other similar drawings.

This and other objects and advantages of the invention will be moreclearly understood from the following description of the preferredembodiments of the invention considered together with the accompanyingdrawing wherein:

3261,98 Patented July 19, 1%86 ice FIGS. 1 and 2 are respectively frontand side elevational views of a complete drafting device according tothe invention;

FIG. 3, is a front elevational view, partly in section, representing amodification of an adapter structure comprising the invention;

FIG. 4 is a partial side elevational view of a modification of thestructure shown in FIG. 3, and

FIGS. 5 and 6 are respectively front and side elevational views, partlyin section, of an adapter structure which features a furthermodification.

As illustrated in FIGS. 1 and 2, the improved drafting instrument hereinis basically a combination of a conventional carriage structure 10, ofthe type disclosed in Patent No. 2,178,755, issued to O. M. Johnson onNovember 7, 1939, and a manipulatable pen support assembly 20. Formingthe carriage structure in this case is a pedestal generally indicated bythe numeral 11, comprising three similar foot elements 12, spaciallyarranged as integral parts of a frame 13, from which rises a forwardlydisposed gooseneck extension 14. Support assembly 20 comprises a bentrod connector 21, which joins a pen adapter structure 25 to a swivelsleeve 26. A clamp-like bracket 30, embracing the swivel sleeve 26, isfastened to an enlarged upper end of the carriage extension 14, withrivets or screws. Swivel sleeve 26 is thereby held vertically disposedin respect to a plane defined by the under surfaces of the carriage footelements 12. Rod element 21 is fixed within sleeve 26 and is angularlydisplaceable therewith relative to bracket 30 which retains the partsplaced therein by reason of a friction fit between the sleeve andbracket. A thumb screw cap 31, fitted to a threaded portion at the upperend of rod 21, facilitates control of the angular displacement of penadapter 25, through its connection with the rod and sleeve.

Pen adapter 25 is fashioned from a rigid sheet material so as to defineopposing wing members 32 and 33, branching out of a cylindrical hangerportion 34. As best seen in FIG. 1, the wing members are symmetricallyarranged about the hanger portion 34 whereby they are situateddownwardly inclined at equal angles from a horizontal plane. Through asuitable opening in wing 32 is received a Rapidograph-type pen 35 whoseink reservoir is attached to a stub part having a threaded section whichextends from a slightly thicker portion 38 of the pen proper and abovethe wing opening. Pen portion 38 is drawn up against the underside ofwing 32 by means of a serrated ferrule 39 screwed down on the threadedsection of the pen stub and into contact with the top side of the wing.In this manner pen 35 is secured to the inclined wing 32 whereby it ismaintained perpendicular thereto. Wing 33 is likewise provided with anopening in which a second pen 36 is secured in the same manner as thatdescribed in connection with pen 35. It is evident therefore thatbecause of the symmetrical arrangement of wings 32 and 33, the pens areheld in positions such that their longitudinal axes are directed tointersect below their writing plane, and whereby their writing tips arespaced apart as required, in this writing plane.

Attachment of the lower end of rod 21 to the adapter 25 is facilitatedby a central opening in the cylindrical hanger 34 of the adapter, inwhich the rod is received and secured by means of an ordinary set screw41. As is evident from the view in FIGURE 2, this lower end of rod 21 isinclined upward at a slight angle of approximately 3 degrees above thehorizontal. Consequently, the hanger connection to rod 21 is effectiveto maintain the adapter and the pens fastened thereto, properly orientedin respect to the base plane of carriage 10. A thumb screw means 42operable in the wall of bracket 30, can be set to engage swivel sleeve26 whereby support assem- 3 bly 20 is fixed facing any predetermineddirection to which it can be displaced.

An angle A shown in FIG. 1 as subtended between the longitudinal axes ofpens 35 and 36, which as hereinbefore noted intersect below the writingplane, can be.

considered indicative of the spacing between the writing tips of thepens. Since the vertical dispositions of the pens shown in FIG. 1 aresubstantially fixed relative to the adapter structure, the spacingbetween the writing tips of the pens can be varied only by changing thespread between the wing members 32 and 33. Angle A which variesinversely with the wing spread of adapter 25, is therefore a measure ofthe space between the lines producible by the pens. Any number ofadapters can be made to constitute a set in which each adapter has adifferent wing spread wherein the pens subtend a different angle A.However, the hanger portion of each adapter must be alike to allow it toreplace any other one of the set that at any time might be in use on thedrafting instrument. This interchangeability is easily accomplished byreason of the simplified set screw connection 41, between the rod 21 andthe adapter structure. In an exemplary structural embodiment of thepresent invention, a line spacing varying from to of an inch wasachieved wherein angle A ranged between 30 degrees and 16 degrees.

FIG. 3 illustrates a modified embodiment of the adapter structurewherein the longitudinal disposition of pens 35 and 36' in respect tothe wing members can be varied in such manner as to change the spacingbetween the writing tips ofthe pens. Since the wing members areangularly disposed downward, and the pens are maintained perpendicularto these members, any axial displacement of the pens will cause theaforementioned change in spacing etween the writing tips. T o facilitatemaking such displacements, the instant embodiment is provided with apair of retainer sleeves 46 and 47 in which are fastened pens 35 and 36,respectively. By referring to the sectional view in FIG. 3, where sleeve46 is shown as an externally threaded tubular element having aninternally threaded collar 48 at one end thereof, it can be seen that athreaded engagement in collar 48 fastens pen 35 thereto, such that thepens ink reservoir extends upwardly through the sleeves tubular element.An opening in wing member 54), which is preferably threaded toaccommodate the ex-' ternal threads of sleeve 46, maintains the latterwhereby it can be axially displaced merely by a rotational adjustmentthereof in the wing member. A pair of lock nuts 52 and 53 may also beprovided to secure the sleeve in its adjusted position. Pen 36 issimilarly fastened in a collar 54 of the sleeve 4-7, whereby this pen iscorrespondingly adjustable relative to wing member 51. Rotation of thesleeves in the wnig members is aided by serrations on collars 48 and 54.In order to return the writing tips to the writing plane following anyaxial adjustment of the pens, it is necessary to make an appropriateaxial adjustment of the swivel sleeve 26, relative to bracket 30.

FIG. 4 illustrates a further modification of the adapter structurewherein a straight rod 56 extending through sleeve 26, is joined to anadapter comprising only substantially flat surfaces. To the rear of thisadapter is a horizontally disposed tab 58, provided with a threaded holein which threads on the end of rod 56 are engageable. Like the adaptershereinbefore described, the adapter of FIGURE 4 is forwardly inclinedslightly upward, and comprises two wing members, one of which isindicated in the figure by the numeral 60. When using this construction,line spacing can be varied as required, by either interchanging adaptersof differing wing spreads as explained in connection with the showing inFIGS. 1 and 2, or by adjusting displaceable retainer sleeves, asindicated in the showing of FIG. 4.

The still further modification of the adapter structure shown in FIGS.and 6, allows a selective variation of the line spacing in the nature ofthat obtained by the interchangeable wing spread feature hereinbeforeexplained in connection with FIGS. 1 and 2. In the case of the instantstructure the spread adjustment is accomplished by means of a screwdrive in which half the length of a flexible rod-like shaft 65 isprovided with a right hand thread, and the other half is provided with aleft hand thread. This drive shaft is operatively supported in a centralportion of the adapter structure, which is seen in FIG. 6 is in arelatively narrow part located to the rear of the adapter. Inparticular, this part comprises left and right body halves 66 and 67separated by a relatively deep, vertically disposed, open slot 68.Passing completely through body halves 66 and 67, are substantiallyrectangular slots 69 and 76 respectively, providing aligned openingsthrough the sides of the body halves. A set of rod-like pivot pins 71and 72 are friction fitted within aligned parallel openings in wallsections of the body halves defined by the slots 69 and 70,respectively, wherein the pivot pins are adapted to rotate slightly.Reversely threaded holes passing transversely through correspondingcentral portions of the cylindrical surfaces of the respective pivotpins, receive therethrough the matching oppositely threaded parts of thedrive shaft 65 A serrated thumb wheel 73 is fastened about the middle ofdrive shaft 65, by means of set screws or pins, whereby the wheel issituated in the middle of slot 68 so that finger gripping surfacesthereof protrude on both sides of the slot. Extending outwardly from theadapter halves and forming integral parts thereof are wing members 74and 75. As is evident from the construction described, wheel 73 can beturned one way or the other, to cause the oppositely sloped threads tospread or retract the adapter halves 66 and 67 about flexible portionsof the adapter structure adjacent the upper end of slot 68. In thismanner the wing spread is changed, and hence the spacing between thewriting tips of the attached pens is altered accordingly.

Because of the inherent simplicity of applying and adjusting the presentinvention for the performance of drafting work ordinarily considereddifiicult, inexperienced draftsmen employing it are enabled to achievehigh quality drawings with lines of uniform weight and widths.

It is evident that reasonable variations and modifications of theembodiments illustrated are possible within the scope of the foregoingdisclosure and the appended claims to the invention.

What is claimed is:

1. A drafting device operable upon a plane drawing surface for producinguniformly spaced double lines on said drawing surface including incombination with a carriage structure displacea'ble over said drawingsurface a manipulatable mean-s maintaining two line drawing means inpredetermined operative positions, said m anipuIat-able means comprisingan element having two parts respectively constituting surfaces in planesequally and oppositely inclined to said drawing surface, said partsbeing adapted thereby to receive therethrough said drawing means, andhold them in said predetermined operative positions, and a shaft means,angularly displaceable about a longitudinal axis thereof disposedperpendicular to said drawing surface, operatively connecting saidelement to said carriage structure, said element further including anextension angularly inclined with respect to said drawing sunface andcentrai'ly arranged between aid parts of said element, an opening insaid extension having detaohaibly fastened therein an extension of saidshaft, whereby said element maintains said drawing means directed towardeach other and away from said shaft in said predetermined operativepositions.

2. The drafting device of claim 1 wherein each said drawing meanscomprises a pen having an enclosed ink reservoir, and said holdingpar-ts each have an opening in which said pens are fastenedperpendicular to the said planes in which the holding parts reside.

3. The drafting device of claim 2 wherein the opening formed in eachsaid holding part contains a sleeve displaceably secured therein, saidsleeves having integrally formed at one end thereof an enlarged section,said draiwing means being retained in said sleeves by means of aconnection therewith in said enlarged sections of said sleeves.

4. The drafting device of claim 1 wherein the centrally arrangedextension of said element comprises a yoke-like member having two spacedapart arms each of which extends from a flexible juncture at anintermediate portion of said member integrally formed with said arms, ahole passing through each of said arms, said holes being aligned witheach other and individually provided with a pivotal element, a furtherhole passing transversely through each element, the respective ones ofsaid further holes having formed therein left and right hand threads, aflexible shaft having left and right halves thereof correspondinglythreaded whereby it is adapted to be operable in said traverse holes toangularly displace said arms in respect to each other, a drive meanscentrally mounted and fiastened on said flexible shaft whereby saiddrive means is located in said space between said arms, saidintermediate portion having said opening in which is fastened saidconnecting shaft means extension.

References Cited by the Examiner UNITED STATES PATENTS 339,817 4/1'886Smitten 334-1 1,181,921 5/1916 Padd-ack 33-41 1,409,037 3/ 1922 Starkeyet al 120- 48 X 2,178,755 11/1'939 Johnson 120-107 2,332,511 10/1943Glassrnan et al 331 8 2,394,4-52 2/1946 Howard 120109.5 2,465,869 3/1949Halstead 33-41 2,557,699 6/1951 Silver 3318 FOREIGN PATENTS 890,7149/1953 Germany.

LEONARD FORMAN, Primary Examiner.

20 ISAAC LISANN, ROBERT B. HULL, Examiners.

WILLIAM D. MARTIN, Assistant Examiner.

1. A DRAFTING DEVICE OPERABLE UPON A PLANE DRAWING SURFACE FOR PRODUCINGUNIFORMLY SPACED DOUBLE LINES ON SAID DRAWING SURFACE INCLUDING INCOMBINATION WITH A CARRIAGE STRUCTURE DISPLACEABLE OVER SAID DRAWINGSURFACE A MANIPULATABLE MEANS MAINTAINING TWO LINE DRAWING MEANS INPREDETERMINED OPERATIVE POSITIONS, SAID MANIPULATABLE MEANS COMPRISINGAN ELEMENT HAVING TWO PART RESPECTIVELY CONSTITUTING SURFACES IN PLANESEQUALLRT OPPOSITELY INCLINED TO SAID DRAWING SURFACE, SAID PARTS BEINGADAPTED THEREBY TO RECEIVE THERETHROUGH SAID DRAWING MEANS, AND HOLDTHEM IN SAID PREDETERMINED OPERATIVE POSITIONS, AND A SHAFT MEANS,ANGULARLY DISPLACEABLE ABOUT A LONGITUDINAL AXIS THEREOF DISPOSEDPERPENDICULAR TO SAID DRAWING SURFACE, OPERATIVELY CONNECTING SAIDELEMENT TO SAID CARRIAGE STRUCTURE, SAID ELEMENT FURTHER INCLUDING ANEXTENSION ANGULARLY INCLINED WITH RESPECT TO SAID DRAWING SURFACE ANDCENTRALLY ARRANGED BETWEEN SAID PARTS OF SAID ELEMENTS, AN OPEN-